nrf52832 sleep ，rtc work

[jwx]

I use the sdk 13.0.0,software device s332，I hope the rtc can work when cpu sleep,and the lowest working current need less than 10uA，what should i do？or Is there a reference routine？

[AmbystomaLabs]

As is the case with most microcontrollers the RTC is the device that allows it to sleep.
So, yes it is on during sleep. The RTC keeps the system clocking while asleep. Then when the system wakes up due to timer or interrupt activity one of the high frequency clocks turns on and it then clocks from that.

Assuming there is no gpio activity, sleep mode with an external crystal RTC can be as little as 2uA or so including RAM retention.

To achieve this you need to write your software correctly to take advantage of all the power saving features of the nRF52832.

The downside of sleeping on the RTC is it takes a little while to wakeup since each cycle is 1/32768 sec. An alternative is a constant latency sleep where the 32MHz is kept on. But it uses more power then.

Here is a good discussion of some of the options and power consumption: devzone.nordicsemi.com/.../

[jwx]

Is there a reference?How to close the protocol stack of clock？

[AmbystomaLabs]

I don't understand your question. The RTC is just a clock there isn't a software stack associated with it. When using a softdevice one normally interfaces with it through softdevice API's, but the RTC is still just hardware.

The nRF spec describes RTC and low power functionality. Here: infocenter.nordicsemi.com/index.jsp

Then if you are interested in the power management API's in the softdevice, then the best resource is the softdevice spec, here: infocenter.nordicsemi.com/index.jsp

Finally here is a tutorial on lower power modes and BLE: devzone.nordicsemi.com/.../

[bjorn-spockeli]

@jwx555: You should also take a look at the RTC driver API, found here.